discoveries magazine

Picture Not Perfect

Emily Swallow for Discoveries Magazine

Emily Swallow’s highly active lifestyle and stressful career could put her at risk for future heart problems. She decompresses by surfing in Venice, California. Photograph: Jessica Chou

Young, athletic women who think they can outrun heart disease need to think again. While the condition is declining in nearly every other demographic, women aged 35–44 are experiencing an alarming increase in heart-related illness.

Chrisandra Shufelt, MD, wants to know why. “Events must be occurring in a woman’s body in her 20s and 30s that impact her heart health in midlife and beyond,” says Shufelt, associate director of the Barbra Streisand Women’s Heart Center at the Smidt Heart Institute and director of its Women’s Hormone and Menopause Program.

Shufelt has a robust hypothesis as to what those events might be. She describes a population of women who unwittingly drive themselves into a state of severely low estrogen through over-exercising, undereating, stress, or a combination of all three.

That estrogen deficiency at a young age is what may lead to heart damage over time: Estrogen is believed to have a positive effect on the inner layer of artery walls, helping to keep blood vessels flexible and increasing blood flow to the heart. This is why risk factors for heart disease increase after menopause when estrogen levels decline.

With funding from the Louis B. Mayer Foundation, Shufelt previously conducted a pilot study of 18 young women. She found that those who stopped menstruating due to low estrogen were beginning to develop dysfunction in the lining of the heart’s blood vessels. Based on that preliminary work, she was awarded a five-year grant by the National Institutes of Health in 2017.

Shufelt’s study is looking at a common cause of low estrogen in young women: functional hypothalamic amenorrhea, the absence of three or more menstrual cycles in a row. For such women, the signal in the brain that controls their menstrual cycle and tells the ovary to release an egg each month shuts down, resulting in low estrogen levels.

This condition affects an estimated 1.6 million women aged 18–44 in the U.S. and some 17.4 million women worldwide.

“A missed period is a signal from the body, but unless these women are trying to get pregnant, they don’t think much of it,” Shufelt says. “I coined the term ‘the walking well’ to describe them because they look very healthy and don’t consider themselves ill, as they are young and active.”

Previous research has shown that extraordinarily active women, such as college athletes, are susceptible to bone loss and fractures due to low estrogen. Until now, however, little has been known about low estrogen’s impact on younger, active women’s heart health.

Shufelt is recruiting three groups of women for her study: those with functional hypothalamic amenorrhea and no periods for at least three months; those who have regular monthly menstrual cycles; and those who have entered menopause within the past three years. Women in the study range in age from their 20s to their 50s.

Fit, driven women of childbearing age are rarely the target of cardiac research. In an era when obesity is epidemic, heart disease is considered a man’s problem, and the zeitgeist suggests that the ideal woman should emulate Sheryl Sandberg at the office and Wonder Woman at the gym, physicians often dismiss otherwise healthy women with irregular menstrual cycles as having nothing to worry about. But not Shufelt.

“We need to get to the bottom of why younger women are developing a potentially deadly condition at higher and higher rates,” she says.


Swallow orders up a salad at Bareburger in Santa Monica, one of the restaurants she coaches as part of her volunteer work in the Ocean Friendly Restaurants Program for the Surfrider Foundation. Photograph: Jessica Chou

Cedars-Sinai investigators believe it is time to look beyond the group that many physicians consider “normal” heart disease sufferers: men.

“I think it speaks volumes that the NIH is sponsoring this study. It’s time to look outside the box of traditional heart risk factors,” Shufelt says.

“We are 50 years behind in our knowledge about optimal screening, diagnoses, and treatment regimens for heart disease in women compared to knowledge about the disease in men,” says C. Noel Bairey Merz, MD, director of the Barbra Streisand Women’s Heart Center and the Linda Joy Pollin Heart Health Program, and the Irwin and Sheila Allen Chair in Women’s Heart Research.

Bairey Merz is a longtime advocate for women’s heart health. Her research has revealed that women’s heart disease looks dramatically different from men’s. In men, large arteries feeding the heart become clogged by plaque that is easy to see on the coronary angiograms used for standard screening. In women, smaller branches tend to lose flexibility and then starve the heart of oxygen— a condition called coronary microvascular dysfunction.

Shufelt compares a woman’s arteries in this condition to the roadways of Los Angeles.

“Imagine the 101 freeway, the 10 freeway, and the 405 are all wide open,” she explains. “Traffic is flowing well. Microvascular dysfunction is where you have bumper-to-bumper traffic on La Cienega, Wilshire, Pico, Olympic—all of those smaller but important arteries. There aren’t any major accidents to clear out, but every light is flashing red.”

Clear medical guidelines support estrogen supplementation in women under the age of 50 who experience early menopause, and older healthy women within 10 years of menopause who struggle with symptoms like hot flashes.

“Estrogen plays an extremely important role in young women, too, in keeping the blood vessels very elastic,” Shufelt says. The good news is that functional hypothalamic amenorrhea is reversible: If a woman cuts back on exercise, gets more calories, or reduces stress, periods can reappear and so does the estrogen. In the latest phase of Shufelt’s research, she is giving women with the condition a transdermal hormone patch in an effort to determine whether this will reverse the early signs of heart disease.

Shufelt also will measure patients’ responses to the estrogen patch, including blood vessel function, bone density, and immune system response.

“Our pilot study showed that low-estrogen states in these young women elevate inflammation markers, which play a role in both immune function and heart disease,” Shufelt says.

Unlike birth control pills, which use synthetic hormones, the estrogen patch is bioidentical, “based on hormones that have the same chemical formula that women’s bodies make,” she says.

She hopes this research will influence gynecologic practice as well. At most visits to the gynecologist’s office, women are asked, “When was your last period?” But that, Shufelt says, might not be the right question.

“Just like blood pressure and heart rate are vital signs, we need to treat the menstrual cycle like a vital sign,” Shufelt says. “We should be asking not just when your last period was but also ‘Are your periods regular?’ Menstrual cycles should happen every month in a young woman and, when they don’t, physicians should determine why.”


Swallow took her conversations with Shufelt to heart, dropping the boot camps, picking up yoga and strength training, and taking a new approach to career stress.

“I have realized that it is more comfortable, in some ways, for me to be constantly in motion and constantly doing,” she says. “Now I consciously make time for things that enrich the non-work parts of my life. I’m not always waiting to see how high the industry wants me to jump.”

Her menstrual cycles have normalized on their own as she tries to hang on to a work-volunteer-exercise-life balance that tends to be hard-won and fleeting for a woman in the prime of life. For Swallow, the ocean is an ally.

“When I get in the water, I can tell how I’m dealing with life based on how I feel about the waves,” she says. “I’ll notice I’m reacting with, ‘No, I don’t think that wave is good, that one looks too big.’ I’ll realize I’m trepidatious. Then the physical act of paddling for the next wave and recognizing that, even if I get tossed around, I’m OK. As cheesy as it sounds, it helps all of me.”


Long the subject of prose and poetry, the human heart has accumulated massive amounts of mythology. While this is fine when discussing romantic metaphors, inaccuracies can become dangerous when circulating about the actual organ on which our survival depends. Below, C. Noel Bairey Merz, MD—director of the Barbra Streisand Women’s Heart Center at the Smidt Heart Institute, director of the Linda Joy Pollin Heart Health Program, and the Irwin and Sheila Allen Chair in Women’s Heart Research—cuts through the figurative plaque to reveal facts and fallacies surrounding women’s heart health.

Fallacy: Heart disease only affects older people.
Fact: “Death rates in women younger than 55 are going up,” Bairey Merz says. “We see women in their early 20s with heart disease.”

Fallacy: Love stories aside, no difference exists between men’s and women’s hearts.
Fact: Until recently, heart disease was considered a man’s disease. Throughout the 1970s and ’80s, clinical trials either excluded women or made little effort to enroll them. Too many researchers believed the only difference between men and women’s hearts was size. But the reality is that heart disease develops differently in women. And, now, more women than men in the United States die of heart disease each year.

“Women’s hearts beat faster, making them more prone to palpitations,” Bairey Merz notes. “Often, women can have open arteries with no blockage or plaque, but the smaller heart arteries have abnormal function.” This difference is particularly dangerous, as the abnormality— called coronary microvascular dysfunction—fails to show up on conventional tests.

Fallacy: Risk factors are the same for men and women.
Fact:Actually, risk factors between the sexes differ as well. Adverse pregnancy outcomes such as gestational diabetes, preeclampsia, and preterm labor have an impact on a woman’s long-term heart health. “Women with these conditions should get regular checkups for cardiac risk counseling,” Bairey Merz says.

Fallacy: The symptoms of heart disease are easy to spot.
Fact: “Don’t expect the ‘Hollywood heart attack,’ where you’re clutching your chest in pain,” Bairey Merz says. “That’s more for men. Some women can get chest pain, but it may not be the first symptom.” Instead, she urges women to take note of any unusual symptom above the waist, “including chest discomfort, indigestion, shortness of breath, arm or jaw discomfort, and extreme fatigue.”